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marsu30@kas.tw: host aspmx.l.google.com[142.250.123.26] said: 550-5.7.1 Kaohsiung American School restricts delivery to student email 550-5.7.1 addresses from outside of our network. If you believe this to be in 550 5.7.1 error, please contact the school directly. - gcdp 00721157ae682-6e2d93e0e51si48794367b3.193 - gsmtp (in reply to end of DATA command)